Positive acting circular chaser die



Sept. 13, 1938. A. E. DRISSNER 2,130,119

POSITIVE ACTING CIRCULAR CHASER DIE Filed May 22, 1937 4 Sheets-Sheet 1g Q @l.

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Sept. 13, 1938.

A. E. DRISSN ER POSITIVE ACTING CIRCULAR CHASER DIE Filed May 22, 1957 4Sheets-Sfieet 2 Sept. 13, 1938. A. E. DRISSNER POSITIVE ACTING CIRCULARCHASER DIE 4 Sheets-Sheet 3 Filed May 22, 1957 Wm m 0 N mm 7 w K m @w/ ml 1 |.v[il!ii V H. .WN [NW1 @N NH QNMVN MN mm Mw Sept. 13, 1938'.

IIIMIF A. E. DRISSNER 2,130,119

POSITIVE ACTING CIRCULAR CHASER DIE Filed May 22, 1957 4 Sheets-Sheet 4I I I Patented Sept. 13, 1938 omen stares ATENT orFmE Alfred E.Drissner, Cleveland, Ohio, assignor to The National Acme Company,Cleveland, Ohio,

a corporation of Ohio Application May 22, 1937, Serial No. 144,228

20 Claims.

This invention relates to threading dies for use on automatic screwmachines, the object of the invention being to provide an improvedpositive acting die in which the cutters or chasers are positivelyexpanded or retracted in an eificient manner and which die is simple inconstruction and operation.

In the drawings accompanying and forming a part of this specification,Fig. 1 is a side View of this improved die.

Fig. 2 is a front end View thereof.

Fig. 3 is a longitudinal sectional view. 7

Fig. 4 is a section on line 4% of Fig. 3, looking in the direction ofthe arrows.

;; Fig. 5 is a perspective View of the cam holder with the cams removed.

Fig. 6 is a perspective view of one of the cams for use in the camholder of Fig. 5.

Fig. 7 is a sectional view on line 'l! of Fig. 1,

looking in the direction of the arrows.

Fig. 8 is a longitudinal section on line 8-8 of Fig. 7, looking in thedirection of the arrows.

Fig. 9 is a detail perspective view of the several parts of the diedisassembled, and

25, Fig. 10 is a perspective view of a chaser block showing in dottedlines a circular chaser applied thereto.

Similar characters of reference indicate corresponding parts in theseveral views.

Before explaining in detail the present improvement and mode ofoperation thereof, I desire to have it understood that the invention isnot limited to the details of construction and arrangement of partsillustrated in the accompanying drawings since the invention is capableof other embodiments, andthat the phraseology employed is for thepurpose of description and not of limitation.

In the preferred form, this improved die comprises a die body 2 havingan enlarged head 3 having radially extending slots A of T-shape thereinfor the reception of similarly formed chaser blocks 5 adapted to carrychasers 6 which are shown herein as of circular form. The die body hasan extended bored shank l for attach- 'ment to suitable holding means ofa screw machine, whereby the die is rotated.

Slidably carried on the body 2 is a hood 8 having an annular recess 9 inthe periphery thereof for the reception of a yoke, not shown, carried bythe machine whereby the hood is shifted back and forth. Within this hood8 is an inwardly projecting annular cam I9 in position to cooperate witha pair of oppositely located segmentally formed shiftable cams l I (seeFig. 4)

' adjustment of this collar toward the chasers, the

having inclined cam faces l2 (see Fig. 6). These cams II are carried inopposed segmental recesses of an annular cam holder or carrier I3located on the inner end of the shank l and within the hood 8. Thesecams are in position to be operated by the cam Ill as the hood isshifted back and forth and are held in projected position by suitablesprings I4 (see Fig. 4) located in opposed faces of the cams and camholder and in their projected position they engage the rear face of anannular sliding ring l5 carried on the cam holder l3 and injuxtaposition to the rear face of the head 3. This ring l5, upon thedepression of the cams II, will be shifted rearwardly on the cam holderl3 by suitable springs 20 located in opposed faces of the ring l5 anddie head 3.

This sliding ring I5 carries a series of longitudinally extending camstuds 16 secured to the ring by pins l6 and adapted to project throughsuitable openings IT in the head 3 and provided with tapered cams orkeys [8 (see Fig. 9). Each of these keys l8 engages a similarly formedcam slot H9 in a chaser block 5 adapted to slide in the radial slot 4 ofthe head 3.

Threaded on the shank l is a collar 24 in position to engage the rearface of the cam holder l3 and hold the parts properly assembled and alsoeffective to adjust the position of the cam holder !3. Adjustment ofthis collar 24 in either direction effects a like movement of this camholder l3, cams ll ring I5, studs l6 and thereby, through the cams orkeys l8, shifts the chaser blocks and their chasers inwardly oroutwardly radially. By

chasers are adjusted to cut a smaller diameter of work. Suitable springsI3 co-operate with the cam holder l3 and rear face of the die body forholding the cam holder in engagement with the collar 24.

A retaining block 25 having an elongated slot 26 is suitably secured onthis collar 24 by means of a screw and limits the backward movement ofthe ring i5 and its associated parts and prevents the keys l8 fromriding beyond the slots 59 in the chaser blocks 5 and thus also preventsthe blocks from falling out of the die. This retaining block 25 may bemoved backward to permit the cams E8 to disengage the slots IQ of theblocks 5 when it is desired to remove the blocks for the insertion ofnew or reground chasers.

Suitably removably secured within the body 2 as by a bayonet joint 21and projecting between the chasers is a work guide member 28 havingprojecting tines 29 extending between the chasers,

to prevent the work falling between the chasers when the die is in openposition.

To insure the positive action of this die, elongated slots 2| (see Fig.3) are provided in the hood 8 and through these slots suitable screws 22project into the ring I5. When the hood 8 contacts these screws 22, theexpanding action of the chasers is started if for any reason the springs20 fail to do this Work. After the expanding action of the chasers isstarted, the springs will complete the expanding action as beforedescribed.

The operation of the die is as follows:

Just before the completion of the threading operation, the yoke carriedby the machine andengaging the hood 8 in the annular recess 9 holds backthe hood as the other parts of the die continue their forward travel.The annular cam III on the inside of the hood rides up the inclinedsurface I2 of the cams I I thereby depressing them within the cam holderI3 against the action of the springs I4. As these cams are pressedwithinthe periphery of the holder I3, the locking action of the camsagainst the rear face of the ring I5 is released and the springs 20acting against the die head 3 force the ring I5 to the ear and with itthe cam rods I6 and due to the sliding action of the keys I8 in slots I9of the blocks 5', the chasers are released form the work.

To reset the die, the spindle is moved backward until the yoke engagingin the groove 9 of the hood 8 is stopped. The body of the die continuesto move back until the flanged face 23 of the hood contacts the rearface of the ring I5 thus holding this ring stationary and permitting thecams II to expand or project outward by means of the springs I4, thuslocking the ring I5 in place.

It is to be understood that, by describing in detail herein anyparticular form, structure or arrangement, it is not intended to limitthe invention beyond the terms of the several claim or the requirementsof the prior art.

Having thus explained the nature of my said invention and described away of constructing and using the same, although without attempting toset forth all of the forms in which itmay be made, or all of the modesof its use, I claim:

1. A threading die comprising a body, a. plurality of radially shiftablechasers and a carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member, both of said means carried by the carrier, and a shiftablehood for controlling the operation of and directly engaging said lockingmeans and effective to release the locking means by depression thereof.

2. A threading die comprising a body, a plurality of radially shiftablechasers and a cam carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member and comprising a shiftable cam, both of said means carriedby the cam carrier, and a shiftable hood for controlling the operationof and directly engaging said locking means and effective to release thelocking means by depression thereof.

3. A threading die comprising a body, a plurality of radially shiftablechasers and a carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member, both of said means carried by the carrier, a shiftable hoodfor controlling the operation of and directly engaging said lockingmeans and effective to release the locking means by depression thereof,and means for adjusting the position of the locking means and therebythe diameter of the chasers.

4. A threading die comprising a body, a plurality of radially shiftablechasers and a cam carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member and com prising a shiftable cam, both of said means carriedby the cam carrier, a shiftable hood for controlling the operation ofand directly engaging said locking means and effective to release thelocking means by depression thereof, and means for adjusting theposition of the locking means and thereby the diameter of the chasers.

5. A threading die comprising a body, a plurality of radially shiftablechasers and a cam carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding ring, said cam carrierprojecting into said ring and provided with shiftable cams for lockingthe ring, and a hood having a cam directly engaging said shiftable camsfor controlling said cams whereby on the depression thereof said ringwill be released to permit sliding thereof.

6. A threading die comprising a body, a plurality of radially shiftablechasers and a cam carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding ring, said cam carrierprojecting into said ring and provided with shiftable cams for lockingthe ring, a hood having a cam directly engaging said shiftable cams forcontrolling said cams whereby on the depression thereof said ring willbe released to permit sliding thereof, and means for adjusting said camcarrier for controlling the diameter of the chasers.

7. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots, a camcarrier encircling said body, positive acting means for shifting theblocks and comprising a sliding ring having forwardly projecting camformed studs co-operating with the slots of the chaser blocks, said camcarrier projecting into said ring and provided with radially shiftablecams for locking the ring, and a shiftable hood having a cam directlyengaging said shiftable cams for controlling the operation of said camswhereby on the depression thereof said ring will be released to permitsliding thereof.

8.- A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots, a camcarrier encircling said body, positive acting means for shifting theblocks and comprising a sliding ring having forwardly projecting camformed studs co-operating with the slots of the chaser blocks, said camcarrier projecting into said ring and provided with radially shiftablecams for locking the ring, a shiftable hood having a cam directlyengaging said shiftable cams for controlling the operationof said camswhereby on the depression thereof said ring will be released to permitsliding thereof, and means for adjusting the cam carrier thereby toadjust the diameter of the chasers carried by the blocks.

9. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots, a camcarrier encircling said body, positive acting means for shiftingtheblocks and comprising a sliding ring having forwardly projecting camformed studs co-operating with-the slots of the chaser blocks, resilientmeans co-operating with the body and ring for shifting the ringrearwardly, said cam carrier projecting into said ring and provided withradially shiftable spring actuated cams for locking the ring, and ashiftable hood having a cam directly engaging said shiftable cams forcontrolling the operation of said cams whereby on the depression thereofsaid ring will be released to permit sliding thereof.

10. A threading die comprising a body, a. plurality of radiallyshiftable chaser carrying blocks carried thereby and having inclinedslots, a cam carrier encircling said body, positive acting means forshifting the blocks and comprising a sliding ring having forwardlyprojecting cam formed studs co-operating with the slots of the chaserblocks, said cam carrier projecting into said ring and provided withradially shiftable cams for locking the ring, a shiftable hood having acam directly engaging said shiftable cams for controlling the operationof said cams whereby on the depression thereof said ring will bereleased to permit sliding thereof, and means co-operating with the ringand the hood for shifting the ring in one direction on the movement ofthe hood.

11. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots, a camcarrier encircling said body, positive acting means for shifting theblocks and comprising a sliding ring having forwardly projecting camformed studs co-operating with the slots of the chaser blocks, said camcarrier projecting into said ring and provided with radially shiftablecams for locking the ring, a shiftable hood having a cam directlyengaging said shiftable cams for controlling the operation of said cams,resilient means co-operating with the body and the ring for shifting thering upon depression of said cams, and means co-operating with the ringand hood for insuring the shifting movement of the ring in onedirection.

12. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots,positive acting means for shifting the blocks and comprising a slidingring having forwardly projecting cam formed studs co-operating with theslots of the chaser blocks, resilient means co-operating with the bodyand ring for shifting the ring, an annular cam carrier carried by thebody and projecting into said ring and provided with radially shiftablespring actuated cams for locking the ring, a shiftable hood having a camdirectly engaging said shiftable cams. for controlling the operation ofsaid cams, whereby on the depression of said spring actuated cams saidsliding ring will be released, means co-operating with the ring and hoodfor insuring the shifting of the ring in one direction on the movementof the hood, and an adjustable collar co-operating with the cam carrierfor adjusting the position of the chaser blocks and thereby the chasers.

13. A threading die comprising a body having a shank, a plurality ofradially shiftable chaser carrying blocks carried by the body and havinginclined slots, positive acting means for shifting the blocks andcomprising a sliding ring having forwardly projecting cam formed studsprojecting through the body and co-operating with the slots of thechaser blocks, an annular cam carrier carried by the shank andprojecting into the ring and provided with radially shiftable cams forlocking the ring, and a shiftable hood having an inwardly extending camdirectly engaging said shiftable cams for controlling the operation ofsaid shiftable cams whereby on the depression thereof said ring will bereleased thereby to permitsliding of said ring.

14. A threading die comprising a body having a shank, a plurality ofradially shiftable chaser carrying blocks carried by the body and havinginclined slots, positive acting means for shifting the blocks andcomprising a sliding ring having forwardly projecting cam formed studsprojecting through the body and co-operating with the slots of thechaser blocks, an annular cam carrier carried by the shank andprojecting into the ring and provided with radially shiftable cams forlocking the ring, a shiftable hood having an inwardly extending camdirectly engaging said shiftable cams for controlling the operation ofsaid shiftable cams whereby on the depression thereof said ring will bereleased thereby to permit sliding of said ring, and an adjustablecollar carried by the shank and in engagement with the cam carrier foradjusting the position thereof and thereby the diameter of the chasers.

15. A threading die comprising a body, a plurality of radially shiftablechasers and a carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member, both of said means carried by the carrier, a shiftable hoodfor controlling the operation of and directly engaging said lockingmeans and eiiective to release the locking means by depression thereof,and work guiding means carried by the body and projecting between thechasers, to prevent the work falling between the chasers when the die isopen.

16. A threading die comprising a body, a plurality of radially shiftablechasers and a carrier carried thereby, positive acting means forshifting the chasers and comprising a sliding member, means for lockingsaid member, both of said means: carried by the carrier, and a shiftablehood for controlling the operation of and directly engaging said lockingmeans and effective to release the locking means by depression thereof,and a detachable work guiding means carried by the body.

17. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried thereby and having inclined slots,positive acting means for shifting the blocks and comprising a slidingring having forwardly projecting camformed studs co-operating with theslots of the chase-r blocks, a cam carrier encircling the body andprojecting into said ring and provided with radially shiftable cams forlocking the ring, a shiftable hood having a cam directly engaging saidshiftable cams for controlling the operation of said cams whereby on thedepression thereof said ring will be released thereby to permit slidingof said ring, and a detachable work guiding means carried by the body.

18. A threading die comprising a body having a shank, a plurality ofradially shiftable chaser carrying blocks carried by the body and havinginclined slots, positive acting means for shifting the blocks andcomprising a sliding ring having forwardly projecting cam formed studsprojecting through the body and co-operating with the slots of thechaser blocks, an annular cam carrier carried by the shank andprojecting .into the ring and provided with radially shiftable cams forlocking the ring, a shiftable hood having an inwardly extending camdirectly engaging said shiftable cams for controlling the operation ofsaid shiftable cams whereby on the depression thereof said ring will bereleased therebyto permit sliding of said ring, and a detachable workguiding means carried by, the body.

19. A threading die comprising a body, a plurality of radially shiftablechaser carrying blocks carried by the body and having wing extensionsadapted to engage the face of the body, a carrier encircling said body,positive acting means for shifting the chasers and comprising a slidingmember, means for locking said member, both of said means carried by thecarrier, and a shiftable hood for controlling the operation of anddirectly engaging said locking means and effective to release thelocking means by depressions thereof.

20. A threading die comprising a body having a shank, a plurality ofradially shiftable chaser carrying blocks carried by the body and havingwing extensions adapted to engage the front face of the body and alsohaving inclined slots,

positive acting means for shifting the blocks and comprising a slidingring having forwardly projecting cam for-med studs. co-operating withthe slots of the, chaser blocks, resilient means cooperating with thebody and ring for shifting the ring rearwardly, an annular cam carriermounted on theshank and projecting into said ring and provided withradially shiftable spring actuated cams for locking the ring, springsco-operating with, the body and cam carrier, a shiftable hood having acam directly engaging said shiftable cams: and effective to depress thecams of the cam carrier and thereby release the stud carrying ringthereby to shift the chasers, and an adjustable collar carried by theshank and cooperating with the cam carrier to adjust the positionthereof and thereby adjust the position of the chasers.

ALFRED E. DRISSNER.

